Arc extinguishing circuit for direct current contactor on fire-fighting robot

Abstract

The arc extinguishing circuit is characterized in that the output end of an on-off key is connected with the first input end of a pre-charging circuit current-limiting resistor, and the output end of the pre-charging circuit current-limiting resistor is connected with the first input end of an STM32 detection control circuit; the first output end of the STM32 detection control circuit is connected with the input end of the pre-charging circuit control circuit, and the output end of the pre-charging circuit control circuit is connected with the contactor; the output end of the battery is connected with the second input end of the pre-charging circuit current-limiting resistor; the input end of the peak voltage detection circuit is connected to the output end of the contactor, and the output end of the peak voltage detection circuit is connected with the second input end of the STM32 detection control circuit; the input end of the absorption circuit is connected to the second output end of the STM32 detection control circuit, and the output end of the absorption circuit is connected to the output end of the contactor. According to the invention, sparks generated during actuation of the contactor can be effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of power supply for fire fighting machines, and in particular to an arc extinguishing circuit for a DC contactor on a fire fighting robot. Background Art

[0002] In modern firefighting and rescue operations, with the continuous advancement of technology and the increasing demand for intelligence, firefighting robots have become an important tool to improve rescue efficiency and ensure the safety of firefighters. Especially in complex or dangerous rescue environments, the role of firefighting robots is particularly important. Therefore, the service life of firefighting robots has become a focus of increasing attention.

[0003] In the prior art, when power is supplied, the contactor connected to the electrical equipment is generally controlled to be closed only through the pre-charging circuit. However, after the contactor is closed, a spike voltage (spark) that is not within a safe range is generated, which reduces the service life of the fire-fighting robot. Therefore, how to control the spike voltage generated after the contactor is closed to be within a safe range has become an urgent problem to be solved. Utility Model Content

[0004] Based on this, in order to solve the above technical problems, an arc extinguishing circuit for a DC contactor on a fire-fighting robot is provided to solve the problem that the existing technology cannot control the internal peak voltage generated after the contactor is attracted within a safe range.

[0005] An arc extinguishing circuit for a DC contactor on a fire-fighting robot, comprising: a pre-charging circuit current limiting resistor, an STM32 detection control circuit, a pre-charging circuit control circuit, a contactor, a switch key, a battery, an absorption circuit and a peak voltage detection circuit;

[0006] The output end of the switch key is connected to the first input end of the pre-charging circuit current limiting resistor, the output end of the pre-charging circuit current limiting resistor is connected to the first input end of the STM32 detection control circuit, the first output end of the STM32 detection control circuit is connected to the input end of the pre-charging circuit control circuit, and the output end of the pre-charging circuit control circuit is connected to a contactor; the output end of the battery is connected to the second input end of the pre-charging circuit current limiting resistor; the output end of the contactor is connected to an electrical device;

[0007] The input end of the peak voltage detection circuit is connected to the output end of the contactor, and the output end of the peak voltage detection circuit is connected to the second input end of the STM32 detection control circuit; the input end of the absorption circuit is connected to the second output end of the STM32 detection control circuit, and the output end of the absorption circuit is connected to the output end of the contactor; the absorption circuit is used to absorb the peak voltage of the contactor.

[0008] In the above scheme, optionally, the circuit also includes: a power supply circuit, which is respectively connected to the pre-charging circuit current limiting resistor, the STM32 detection control circuit, the pre-charging circuit control circuit, the contactor, the absorption circuit and the peak voltage detection circuit.

[0009] In the above solution, optionally, the absorption circuit includes: a resistor R8, a resistor R9, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a MOS transistor Q2, a MOS transistor Q3, a transistor Q4 and a transistor Q5;

[0010] The emitter of the transistor Q5 is connected to the resistor R13 and the collector of the transistor Q4 in sequence;

[0011] The gate of the MOS transistor Q2 is connected to one end of the resistor R8, a first node is set on the connection line between the gate of the MOS transistor Q2 and the resistor R8, a first branch is drawn from the first node to connect one end of the resistor R11, and the other end of the resistor R11 is connected to the source of the MOS transistor Q2;

[0012] The gate of the MOS transistor Q3 is connected to one end of the resistor R9, a second node is set on the connection line between the gate of the MOS transistor Q3 and the resistor R9, a second branch is drawn from the second node to connect one end of the resistor R12, and the other end of the resistor R12 is connected to the source of the MOS transistor Q3;

[0013] One end of the resistor R14 is connected to pin 2 of the 4-pin terminal, and the other end of the resistor R14 is connected to pin 1 of the 4-pin terminal; pin 3 and pin 2 of the 4-pin terminal are connected;

[0014] A third node is set on the connection line between the resistor R13 and the collector of the transistor Q4, and a third branch is drawn from the third node to connect the other end of the resistor R8 and the other end of the resistor R9;

[0015] The drain of the MOS tube Q2 and the drain of the MOS tube Q3 are connected to the connection line between the resistor R14 and the pin 1 of the 4-pin terminal.

[0016] In the above solution, further optionally, the resistance of the resistor R14 is 3Ω to 8Ω, and the power is 50-200W.

[0017] In the above solution, further optionally, the model of the resistor R14 is RX24 gold resistor.

[0018] In the above solution, further optionally, the model of the MOS tube Q2 and the MOS tube Q3 is NCE85H21C.

[0019] In the above solution, optionally, the peak voltage detection circuit includes a resistor R1, a resistor R2, a resistor R3 and a capacitor C1;

[0020] One end of the resistor R2 is connected to one end of the resistor R3, a fourth node is set on the connecting line between the resistor R2 and the resistor R3, a fourth branch and a fifth branch are led out from the fourth node, the fourth branch is connected to the resistor R1, the fifth branch is connected to one end of the capacitor C1, the other end of the resistor R2 is connected to the other end of the capacitor C1; the other end of the resistor R3 is connected to the STM32 detection control circuit.

[0021] This application has at least the following beneficial effects:

[0022] When the robot is powered on, the pre-charging circuit current limiting starts to work and the battery voltage is limited and then slowly rises to the set value. When the set value is reached, the STM32 control circuit controls the relay to close the contactor. The peak voltage detection circuit detects the peak voltage of the contactor. When the peak voltage generated at the moment of contactor closing is higher than the battery voltage, the absorption circuit works to absorb the peak voltage. This method of absorption circuit can effectively reduce the sparks generated when the contactor is closed and increase the service life of the fire fighting robot. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A structural block diagram of an arc extinguishing circuit for a DC contactor on a fire-fighting robot provided in one embodiment of the present application;

[0024] Figure 2 A circuit schematic diagram of a pre-charging circuit current limiting resistor and a pre-charging circuit control circuit provided in one embodiment of the present application;

[0025] Figure 3 A circuit schematic diagram of a peak voltage detection circuit and an STM32 detection control circuit provided in one embodiment of the present application;

[0026] Figure 4 A schematic diagram of a power supply circuit provided for one embodiment of the present application;

[0027] Figure 5 A schematic diagram of an absorption circuit provided for one embodiment of the present application. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0029] In one embodiment, Figure 1As shown, an arc extinguishing circuit for a DC contactor on a fire-fighting robot is provided, comprising: a pre-charging circuit current limiting resistor, an STM32 detection control circuit, a pre-charging circuit control circuit, a contactor, a switch key, a battery, an absorption circuit, and a peak voltage detection circuit;

[0030] The output end of the switch key is connected to the first input end of the pre-charging circuit current limiting resistor, the output end of the pre-charging circuit current limiting resistor is connected to the first input end of the STM32 detection control circuit, the first output end of the STM32 detection control circuit is connected to the input end of the pre-charging circuit control circuit, and the output end of the pre-charging circuit control circuit is connected to a contactor; the output end of the battery is connected to the second input end of the pre-charging circuit current limiting resistor; the output end of the contactor is connected to an electrical device;

[0031] The input end of the peak voltage detection circuit is connected to the output end of the contactor, and the output end of the peak voltage detection circuit is connected to the second input end of the STM32 detection control circuit; the input end of the absorption circuit is connected to the second output end of the STM32 detection control circuit, and the output end of the absorption circuit is connected to the output end of the contactor; the absorption circuit is used to absorb the peak voltage of the contactor.

[0032] Specifically, if Figure 2 As shown, it is the circuit schematic diagram of the pre-charging circuit current limiting resistor and the pre-charging circuit control circuit. Figure 2 S1 is the switch key, K1 is the contactor, and R4 is the current limiting resistor of the pre-charge circuit.

[0033] Figure 3 This is the circuit schematic diagram of the peak voltage detection circuit and the STM32 detection control circuit.

[0034] In the arc extinguishing circuit of the DC contactor used in the fire-fighting robot, the pre-charging circuit current limiting resistor starts to work to limit the battery voltage and then slowly rises to the set value. When the set value is reached, the STM32 control circuit controls the relay to close the contactor, and the peak voltage detection circuit detects the peak voltage of the contactor. When the peak voltage generated at the moment of contactor closing is higher than the battery voltage, the absorption circuit works to absorb the peak voltage. The absorption circuit method can effectively reduce the sparks generated when the contactor is closed and increase the service life of the fire-fighting robot.

[0035] In one embodiment, the circuit further comprises: a power supply circuit such as Figure 4 The power supply circuit is shown in the figure. The power supply circuit is respectively connected to the pre-charging circuit current limiting resistor, the STM32 detection control circuit, the pre-charging circuit control circuit, the contactor, the absorption circuit and the peak voltage detection circuit.

[0036] In one embodiment, Figure 5 As shown, the absorption circuit includes: a resistor R8, a resistor R9, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a MOS transistor Q2, a MOS transistor Q3, a transistor Q4 and a transistor Q5;

[0037] The emitter of the transistor Q5 is connected to the resistor R13 and the collector of the transistor Q4 in sequence;

[0038] The gate of the MOS transistor Q2 is connected to one end of the resistor R8, a first node is set on the connection line between the gate of the MOS transistor Q2 and the resistor R8, a first branch is drawn from the first node to connect one end of the resistor R11, and the other end of the resistor R11 is connected to the source of the MOS transistor Q2;

[0039] The gate of the MOS transistor Q3 is connected to one end of the resistor R9, a second node is set on the connection line between the gate of the MOS transistor Q3 and the resistor R9, a second branch is drawn from the second node to connect one end of the resistor R12, and the other end of the resistor R12 is connected to the source of the MOS transistor Q3;

[0040] One end of the resistor R14 is connected to pin 2 of the 4-pin terminal, and the other end of the resistor R14 is connected to pin 1 of the 4-pin terminal; pin 3 and pin 2 of the 4-pin terminal are connected;

[0041] A third node is set on the connection line between the resistor R13 and the collector of the transistor Q4, and a third branch is drawn from the third node to connect the other end of the resistor R8 and the other end of the resistor R9;

[0042] The drain of the MOS tube Q2 and the drain of the MOS tube Q3 are connected to the connection line between the resistor R14 and the pin 1 of the 4-pin terminal.

[0043] In one embodiment, the resistance of the resistor R14 is 3Ω-8Ω and the power is 50-200W.

[0044] In the above solution, further optionally, the model of the resistor R14 is RX24 gold resistor.

[0045] In one embodiment, the MOS transistor Q2 and the MOS transistor Q3 are of model NCE85H21C.

[0046] In one embodiment, Figure 3 As shown, the peak voltage detection circuit includes a resistor R1, a resistor R2, a resistor R3 and a capacitor C1;

[0047] One end of the resistor R2 is connected to one end of the resistor R3, a fourth node is set on the connecting line between the resistor R2 and the resistor R3, a fourth branch and a fifth branch are led out from the fourth node, the fourth branch is connected to the resistor R1, the fifth branch is connected to one end of the capacitor C1, the other end of the resistor R2 is connected to the other end of the capacitor C1; the other end of the resistor R3 is connected to the STM32 detection control circuit.

[0048] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0049] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the utility model patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. An arc extinguishing circuit for a DC contactor on a fire-fighting robot, characterized in that: include: Pre-charging circuit current limiting resistor, STM32 detection control circuit, pre-charging circuit control circuit, contactor, switch key, battery, absorption circuit and peak voltage detection circuit; The output end of the switch key is connected to the first input end of the pre-charging circuit current limiting resistor, the output end of the pre-charging circuit current limiting resistor is connected to the first input end of the STM32 detection control circuit, the first output end of the STM32 detection control circuit is connected to the input end of the pre-charging circuit control circuit, and the output end of the pre-charging circuit control circuit is connected to a contactor; the output end of the battery is connected to the second input end of the pre-charging circuit current limiting resistor; the output end of the contactor is connected to an electrical device; The input end of the peak voltage detection circuit is connected to the output end of the contactor, and the output end of the peak voltage detection circuit is connected to the second input end of the STM32 detection control circuit; the input end of the absorption circuit is connected to the second output end of the STM32 detection control circuit, and the output end of the absorption circuit is connected to the output end of the contactor; the absorption circuit is used to absorb the peak voltage of the contactor.

2. The arc extinguishing circuit of the DC contactor for the fire fighting robot according to claim 1, characterized in that: The circuit also includes: a power supply circuit, which is respectively connected to the pre-charging circuit current limiting resistor, the STM32 detection control circuit, the pre-charging circuit control circuit, the contactor, the absorption circuit and the peak voltage detection circuit.

3. The arc extinguishing circuit of the DC contactor for the fire fighting robot according to claim 1, characterized in that: The absorption circuit includes: a resistor R8, a resistor R9, a resistor R11, a resistor R12, a resistor R13, a resistor R14, a MOS transistor Q2, a MOS transistor Q3, a transistor Q4 and a transistor Q5; The emitter of the transistor Q5 is connected to the resistor R13 and the collector of the transistor Q4 in sequence; The gate of the MOS transistor Q2 is connected to one end of the resistor R8, a first node is set on the connection line between the gate of the MOS transistor Q2 and the resistor R8, a first branch is drawn from the first node to connect one end of the resistor R11, and the other end of the resistor R11 is connected to the source of the MOS transistor Q2; The gate of the MOS transistor Q3 is connected to one end of the resistor R9, a second node is set on the connection line between the gate of the MOS transistor Q3 and the resistor R9, a second branch is drawn from the second node to connect one end of the resistor R12, and the other end of the resistor R12 is connected to the source of the MOS transistor Q3; One end of the resistor R14 is connected to pin 2 of the 4-pin terminal, and the other end of the resistor R14 is connected to pin 1 of the 4-pin terminal; pin 3 and pin 2 of the 4-pin terminal are connected; A third node is set on the connection line between the resistor R13 and the collector of the transistor Q4, and a third branch is drawn from the third node to connect the other end of the resistor R8 and the other end of the resistor R9; The drain of the MOS tube Q2 and the drain of the MOS tube Q3 are connected to the connection line between the resistor R14 and the pin 1 of the 4-pin terminal.

4. The arc extinguishing circuit of the DC contactor for the fire fighting robot according to claim 3, characterized in that: The resistance of the resistor R14 is 3Ω to 8Ω, and the power is 50-200W.

5. The arc extinguishing circuit of the DC contactor used in the fire fighting robot according to claim 4, characterized in that: The resistor R14 is a RX24 gold resistor.

6. The arc extinguishing circuit of the DC contactor used in the fire fighting robot according to claim 3, characterized in that: The models of the MOS tube Q2 and the MOS tube Q3 are NCE85H21C.

7. The arc extinguishing circuit of the DC contactor for the fire fighting robot according to claim 1, characterized in that: The peak voltage detection circuit includes a resistor R1, a resistor R2, a resistor R3 and a capacitor C1; One end of the resistor R2 is connected to one end of the resistor R3, a fourth node is set on the connecting line between the resistor R2 and the resistor R3, a fourth branch and a fifth branch are led out from the fourth node, the fourth branch is connected to the resistor R1, the fifth branch is connected to one end of the capacitor C1, the other end of the resistor R2 is connected to the other end of the capacitor C1; the other end of the resistor R3 is connected to the STM32 detection control circuit.

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